Last month Mars Rover Opportunity celebrated its tenth anniversary on the red (brown?) planet by snapping a selfie and sending it home. How does it look? It has suffered from the scarcity of local carwashes, but despite the dust buildup, the rover has aged remarkably well.
Think of what were you driving ten years ago…does it run as well as Opportunity still does? Although its twin Spirit got stuck and stopped answering calls in 2010, Opportunity remains active as a low mileage (tens of millions of km flown, but under 40 km on the ground) prestige vehicle that has been very carefully driven.
Opportunity’s continued opp-eration is a testament to the incredibly robust system designed by NASA/JPL. It’s one thing to have the latest, gaudiest performance specs; it’s quite another to deliver on your performance for more than 40 times longer than the original spec with no chance of maintenance.
Designing a long lifespan for a product requires engineers to optimize for different priorities. According to Wikipedia, Opportunity’s onboard computer uses a 20 MHz RAD6000 CPU with 128 MB of DRAM, 3 MB of EEPROM, and 256 MB of flash memory–not raw performance numbers that would impress an aficionado even a dozen years ago, but I think we can all recognize and appreciate the primacy of “design for reliability” in this case. Computers are notoriously quick to evolve into obsolescence (every 18 months or so I’m told, and while machine vision systems may iterate at a slower rate, how many of us would expect to install systems today and see them running smoothly ten years on?
Opportunity’s components (thousands and thousands of them) and systems were all designed, simulated, tested, characterized, tested, integrated, tested, and um, re-tested with obsessive-compulsive attention to detail by people who took pride in their work and thought about the long term. When so many of the technology products we buy (and sell) today are intended to be disposable and intentionally replaceable, it is refreshing to consider things built to last. (Full disclosure: Teledyne DALSA has skin in this game, having manufactured the image sensors on the rovers’ Hazcams and Navcams). Granted, Opportunity is ultimately also disposable (sadly nobody is going to go retrieve it), but it is definitely not replaceable. Opportunity and its designers deserve not just a slow clap but a full-throated standing ovation*. Long may it continue…it and its younger sibling Curiosity.
You can follow more adventures of all the Mars rovers at http://marsrover.nasa.gov/home/index.html
*(and so, it should be said, does Spirit, which didn’t burn out as much as it faded away—stuck in terrain that could only be guessed at during its design phase, Spirit eventually ran out of power because of the buildup of dust on its solar panels and the fact it couldn’t reach a location with more solar exposure).